What type of agreement to secure an intent to buy?

I worked with a new partner to create a customer before we signed a var agreement.(we had a NDA though)

We sold the customer our software but the actual contract for the sale will not take place till Q3 because its public sector procurement process.The sale must be under the umbrella of the reseller for various reasons so we need to sell it to the reseller , reseller sells to customer.

Now the partner has decided that they don't want to resell for anyone right now but will maintain their commitment to see it through this one sale we did. They are in control of getting the contract with the customer etc.. What type of agreement should we have with them to secure this one deal and that the contract will occur?

As nobody's biting at this question, I'll give an I-am-not-a-lawyer-nor-could-I-play-one-on-TV answer.

It sounds like you need a simple contract - this could be nothing more than a letter, signed by both parties, stating what each party promises to do and what consideration (e.g. money) one party will give the other as a result.

Lawyers like to add covering all the eventualities they can think of: What happens if one party dies? What happens if the sales isn't made? What happens if one party defaults? What happens if a company is sold? What happens if the sale isn't made? What happens if the sale isn't made for fifty years? What happens if the price changes? Where should a legal dispute be settled? Should binding arbitration be used instead of a court case?

Add clauses (paragraphs) which cover anything you think might happen - probably in this case it's no more than "if the sale doesn't happen within two years, this agreement is void."

Then if there is a significant amount of money / liability involved, pay a lawyer to review the agreement before you both sign and date it. Once both parties have indicated their acceptance (typically by signing and dating it), then it's a contract.

Please note: I'm not a lawyer and am only vaguely recalling what I learned while helping a friend pass their accountancy exams a long, long, time ago in a place far away...